Modified blasting agent

Abstract

The present invention relates generally to an explosive composition comprising an aqueous emulsion of: an oxidizer component, a hydrocarbon fuel component containing emulsifier, and a bulking agent being a fuel-type waste material in a solid particulate form substantially lacking rough surfaces and sharp edges. Preferably the composition is of an ammonium nitrate based emulsion and a pelletised bulking agent. It also involves a method of providing an explosive composition to a blast site using a conventional mobile processing unit (MPU), being a truck having separate compartments adapted for holding fuel oil, dry ammonium nitrate prill, and ammonium nitrate based emulsion, where a compartment instead holds particulate waste material. It also concerns a method of blasting soft and wet ground, which comprises injecting into one or more blast holes in the soft and wet ground a sufficient quantity of the composition, and then setting off the composition.

1 - 18 . (canceled) 
     
     
         19 . A method of delivering an explosive composition, comprising:
 providing a mobile processing unit (MPU), comprising a truck having at least three separate compartments:
 a first compartment storing a fuel component; 
 a second compartment configured for holding dry ammonium nitrate prill, but storing a waste material, wherein the waste material is an inert solid particulate recycled plastic waste material formed into smooth, dry pellets with rounded corners and edges and having an average size and shape and flowability substantially the same as ammonium nitrate prill and the inert solid particulate recycled waste material having a density of around 0.2 to 1.0 g/cm 3 ; and 
 a third compartment storing an ammonium nitrate-based emulsion (ANE) comprising: 
 (i) a discontinuous phase comprising ammonium nitrate; and 
 (ii) a continuous phase comprising a fuel component; 
   mixing waste material from the second compartment with ANE from the third compartment and optionally with fuel component from the first compartment to form a first mixture comprising at least 50% ANE;   adding a density reducing agent to the first mixture to sensitize the first mixture and form an explosive composition prior to delivering the explosive composition into a blast hole; and   delivering the explosive composition into a blast hole.   
     
     
         20 . The method of  claim 19 , wherein the fuel component comprises diesel oil and an emulsifier. 
     
     
         21 . The method of  claim 19 , wherein the waste material does not promote crystallisation of the ANE resulting in destabilisation of the ANE, and wherein the presence of the waste material alone neither provides a source of ignition nor any sensitisation to the ANE to permit an explosion. 
     
     
         22 . The method of  claim 19 , wherein delivering the explosive composition comprises augering the explosive mixture. 
     
     
         23 . The method of  claim 19 , wherein the blasthole is arranged in soft and wet ground and the method further comprises the steps of:
 delivering a sufficient quantity of the explosive composition into the blast hole; and   setting off the explosive composition.   
     
     
         24 . The method of  claim 23 , further comprising identifying or having identified the blast hole as being in ground that is soft, wet, or both. 
     
     
         25 . The method of  claim 19 , wherein the density reducing agent comprises a salt of sodium nitrite, which generate nitrogen gas when combined with ANE. 
     
     
         26 . The method of  claim 19 , wherein the density of the explosive composition is reduced to 0.80 to 1.15 g/cm 3  by addition of the density reducing agent. 
     
     
         27 . The method of  claim 19 , wherein the waste material has an average particle size of about 2 to 3 mm. 
     
     
         28 . The method of claim  1 , wherein about 1% to 50% by weight of the total composition of waste material comprises recycled plastics material 
     
     
         29 . The method of  claim 19 , wherein the waste material comprises from 10% to 40% by weight of the total composition. 
     
     
         30 . The method of  claim 19 , wherein the waste material comprises a recycled waste material melted or compressed together and then extruded into dry pellets with rounded corners and edges. 
     
     
         31 . A method of blasting, comprising:
 providing a mobile processing unit (MPU), comprising a truck having at least three separate compartments:
 a first compartment storing a fuel component; 
 a second compartment configured for holding dry ammonium nitrate prill, but storing a waste material, wherein the waste material is an inert solid particulate recycled plastic waste material formed into smooth, dry pellets with rounded corners and edges and having an average size and shape and flowability substantially the same as ammonium nitrate prill and the inert solid particulate recycled waste material having a density of around 0.2 to 1.0 g/cm 3 ; and 
 a third compartment storing an ammonium nitrate-based emulsion (ANE) comprising: 
 (i) a discontinuous phase comprising ammonium nitrate; and 
 (ii) a continuous phase comprising a fuel component; 
   determining if a blast hole is located in ground that is soft, wet, or both;
 if yes, then mixing waste material from the second compartment with ANE from the third compartment and optionally with fuel component from the first compartment to form a first mixture comprising at least 50% ANE; and adding a density reducing agent to the first mixture to sensitize the first mixture and form an explosive composition prior to delivering the explosive composition into the blast hole; 
 if no, adding a density reducing agent to the first mixture to sensitize the first mixture and form an explosive composition prior to delivering the explosive composition into the blast hole; and 
   delivering the explosive composition into the blast hole.   
     
     
         32 . The method of  claim 19 , wherein the fuel component comprises diesel oil and an emulsifier. 
     
     
         33 . The method of  claim 19 , wherein the waste material does not promote crystallisation of the ANE resulting in destabilisation of the ANE, and wherein the presence of the waste material alone neither provides a source of ignition nor any sensitisation to the ANE to permit an explosion. 
     
     
         34 . The method of  claim 19 , wherein the density reducing agent comprises a salt of sodium nitrite, which generate nitrogen gas when combined with ANE. 
     
     
         35 . The method of  claim 19 , wherein the waste material has an average particle size of about 2 to 3 mm. 
     
     
         36 . The method of claim  1 , wherein about 1% to 50% by weight of the total composition of waste material comprises recycled plastics material. 
     
     
         37 . The method of  claim 19 , wherein the waste material comprises from 10% to 40% by weight of the total composition. 
     
     
         38 . The method of  claim 19 , wherein the waste material comprises a recycled waste material melted or compressed together and then extruded into dry pellets with rounded corners and edges.